package cn.com.fstar.core.util;

import org.apache.commons.lang.StringUtils;

/**
 * 中文转换为英文字母
 * 
 * @author NOLY DAKE
 * 
 */
public class ChineseCharToEn {

    public final static char OTHER_CHAR = 'V';

    /**
     * 
     * @param args
     */

    public static String getFristLetter(String strChinese) {
        String letter = getPYIndexStr(strChinese, true);
        if (StringUtils.isNotEmpty(letter)) {
            return StringUtils.substring(letter, 0, 1);
        }
        return null;
    }

    /**
     * 
     * 返回每个字的首字母
     * 
     * @param strChinese
     * 
     * @param bUpCase
     * 
     * @return
     */

    private static String getPYIndexStr(String strChinese, boolean bUpCase) {

        if (strChinese == null) {
            return null;
        }

        try {

            StringBuffer buffer = new StringBuffer();

            byte b[] = strChinese.getBytes("GBK");// 把中文转化成byte数组

            for (int i = 0; i < b.length; i++) {

                if ((b[i] & 255) > 128) {

                    int char1 = b[i++] & 255;

                    char1 <<= 8;// 左移运算符用“<<”表示，是将运算符左边的对象，向左移动运算符右边指定的位数，并且在低位补零。其实，向左移n位，就相当于乘上2的n次方

                    int chart = char1 + (b[i] & 255);

                    buffer.append(getPYIndexChar((char) chart, bUpCase));

                    continue;

                }

                char c = (char) b[i];

                if (!Character.isJavaIdentifierPart(c))// 确定指定字符是否可以是 Java
                                                       // 标识符中首字符以外的部分。

                    c = OTHER_CHAR;

                buffer.append(c);

            }
            return buffer.toString().toUpperCase();

        } catch (Exception e) {

            System.out.println((new StringBuilder()).append("\u53D6\u4E2D\u6587\u62FC\u97F3\u6709\u9519")
                    .append(e.getMessage()).toString());

        }

        return null;

    }

    /**
     * 
     * 得到首字母
     * 
     * @param strChinese
     * 
     * @param bUpCase
     * 
     * @return
     */

    private static char getPYIndexChar(char strChinese, boolean bUpCase) {

        int charGBK = strChinese;

        char result;

        if (charGBK >= 45217 && charGBK <= 45252) {
            result = 'A';
        } else if (charGBK >= 45253 && charGBK <= 45760) {
            result = 'B';
        } else if (charGBK >= 45761 && charGBK <= 46317) {
            result = 'C';
        } else if (charGBK >= 46318 && charGBK <= 46825) {
            result = 'D';
        } else if (charGBK >= 46826 && charGBK <= 47009) {
            result = 'E';
        } else if (charGBK >= 47010 && charGBK <= 47296) {
            result = 'F';
        } else if (charGBK >= 47297 && charGBK <= 47613) {
            result = 'G';
        } else if (charGBK >= 47614 && charGBK <= 48118) {
            result = 'H';
        } else if (charGBK >= 48119 && charGBK <= 49061) {
            result = 'J';
        } else if (charGBK >= 49062 && charGBK <= 49323) {
            result = 'K';
        } else if (charGBK >= 49324 && charGBK <= 49895) {
            result = 'L';
        } else if (charGBK >= 49896 && charGBK <= 50370) {
            result = 'M';
        } else if (charGBK >= 50371 && charGBK <= 50613) {
            result = 'N';
        } else if (charGBK >= 50614 && charGBK <= 50621) {
            result = 'O';
        } else if (charGBK >= 50622 && charGBK <= 50905) {
            result = 'P';
        } else if (charGBK >= 50906 && charGBK <= 51386) {
            result = 'Q';
        } else if (charGBK >= 51387 && charGBK <= 51445) {
            result = 'R';
        } else if (charGBK >= 51446 && charGBK <= 52217) {
            result = 'S';
        } else if (charGBK >= 52218 && charGBK <= 52697) {
            result = 'T';
        } else if (charGBK >= 52698 && charGBK <= 52979) {
            result = 'W';
        } else if (charGBK >= 52980 && charGBK <= 53688) {
            result = 'X';
        } else if (charGBK >= 53689 && charGBK <= 54480) {
            result = 'Y';
        } else if (charGBK >= 54481 && charGBK <= 55289) {
            result = 'Z';
        } else {
            result = OTHER_CHAR;
        }

        if (!bUpCase) {
            result = Character.toLowerCase(result);
        }

        return result;

    }

}